60’s Tube Organ Tear Down and Recycle

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The "tubes" are probably neon lamps used as perhaps a sawtooth oscillator.

https://en.wikipedia.org/wiki/Pearson–Anson_effect

Bri
Indeed they are. The circuit is a frequency divider.
Looking again at the pic showing apparently neon bulbs, I count 12 very similar sections. Top octave generator? But how is it tuned....lol

Bri
They don't need to be tuned, since they follow the master oscillator. Each section is a divide by two. The master oscillator delivers the top octave and the dividers deliver the octaves below.
Master oscillators are apparently tuned by adjusting the nuts on the inductors.
nuts.jpg
 
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I am far from an electronic organ expert, but SOMEWHERE in that Conn is a top octave generator. The card with the neons seemed logical since it had twelve "identical" sections. Just guessing that the portion with the multiple 12AU7 bottles were the octave dividers.

Shrug.....

Bri
 
What a massive oscillators array !

To me this is not neon tube for octave divider purpose like we can see on Philocorda, but a full 6 octaves single OSC per note.

If you look close this is probably double triode (not neon) with 2 tuning self and 2 oscillator per tube...72 LC single triode oscillators !!! and the back confirm the noval socket

You can also see notes label on the side plate with chromatic pattern and not octaves pattern.

Now it's probably to late...but a restoration is preferable to a tear down... at least that what I'll do if I'll get such instrument, which dose not prevent mod to add preamp and extra input for guitar or whatever to access the amp, speaker and leslie.

If a tear down is mandatory, I'll try to keep the whole OSC section intact, and try to make a crazy drone synth with it !!!
Just imagine the sound of 72 osc with crazy tuning....
 
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